Here, we broke down all the tools and knowledge needed to properly solder and desolder components via THT (Through-Hole Technology).

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- #2487
- 10 Sep 2025
Tools & Materials You’ll Need:
Soldering Iron.
Solder.
Soldering Iron Stand.
Sponge or Brass Tip Cleaner.
Wire Cutters.
Helping Hands / PCB Holder.
Flux.
Safety First:
Always work in a well-ventilated area.
Never touch the tip of the soldering iron.
Use a stand to avoid accidents, even if you are confident in your abilities with the soldering iron.
The Soldering Step-by-Step:
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Prep Your Workspace
- Clear your work area, plug in your soldering iron, and let it heat up (usually 2–3 minutes).
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Tin the Tip
- Once hot, melt a little solder onto the iron tip. This is called tinning, and it helps transfer heat better.
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Prepare Components
- Insert the component leads into the correct holes on the PCB.
- Flip the board and bend the leads slightly to hold the component in place.
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Apply Heat
- Touch the soldering iron tip to both the lead and the copper pad on the PCB simultaneously.
- Heat for 1–2 seconds.
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Feed the Solder
- Feed solder into the joint (not directly onto the iron).
- Let it flow around the lead and pad.
- Remove the solder, then the iron.
Total heating time: Around 2–3 seconds. Too long can damage components or the board.
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Inspect the Joint
- Look for a shiny, cone-shaped joint that covers both the lead and pad. It should be smooth, not blob-like or dull.
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Trim Excess Leads
- Use wire cutters to trim the leads flush with the solder.
Desoldering (Fixing Mistakes):
Cock the pump by pressing down on the plunger until it locks into place
Heat the joint.
Press the pump trigger (on the side) while removing the iron.
Cleanup & Maintenance:
Always clean the iron tip after use.
Unplug and let it cool before storing.
Keep solder sealed when not in use to avoid oxidation.